Configuring a tts platform

Depending on your setup, you might need to set a base URL (base_url) inside the http component or in the parameters of this component.

The following optional parameters can be used with any platform. However, the TTS integration will only look for global settings under the configuration of the first configured platform:

Configuration Variables

cache

(boolean)(Optional)

Allow TTS to cache voice file to local storage.

Default value:

true

cache_dir

(string)(Optional)

Folder name or path to a folder for caching files.

Default value:

tts

time_memory

(integer)(Optional)

Time to hold the voice data inside memory for fast play on a media player. Minimum is 60 s and the maximum 57600 s (16 hours).

Default value:

300

base_url

(string)(Optional)

A base URL to use instead of the one set in the http component. It is used as-is by the tts component. In particular, you need to include the protocol scheme http:// or https:// and the correct port number. They will not be automatically added for you.

Default value:

value of http.base_url

service_name

(string)(Optional)

Define the service name.

Default value:

The service name default set to _say. For example, for google_translate tts, its service name default is google_translate_say.

In the above example, base_url is custom to this particular TTS platform configuration. It is not suggesting that you use the base_url that you have set for your core Home Assistant configuration. The reason you might need to do this is outlined in the next section.

When do you need to set base_url here?

The general answer is “whenever the global base_url set in http component is not adequate to allow the say service to run”. The say service operates by generating a media file that contains the speech corresponding to the text passed to the service. Then the say service sends a message to the media device with a URL pointing to the file. The device fetches the media file at the URL and plays the media. Some combinations of a media device, network configuration and Home Assistant configuration can make it so that the device cannot fetch the media file.

The following sections describe some of the problems encountered with media devices.

Self-signed certificates

This problem occurs when your Home Assistant instance is configured to be accessed through SSL, and you are using a self-signed certificate.

The tts service will send an https:// URL to the media device, which will check the certificate, and reject it. So it won’t play your file. If you could make the device accept your certificate, it would play the file. However, many media devices do not allow changing settings to accept self-signed certificates. Ultimately, your option may be to serve files to the device as http:// rather than https://. To do this, you could change the base_url setting in http component, but that would turn off SSL for all services that use base_url. Instead, setting a base_url for the tts service allows turning off SSL only for this component.

Google cast devices

They do not work with URLs that contain hostnames established by local naming means. Let’s say your Home Assistant instance is running on a machine made known locally as ha. All your machines on your local network are able to access it as ha. However, try as you may, your cast device won’t download the media files from your ha machine. That’s because your cast device ignores your local naming setup. In this example, the say service creates a URL like http://ha/path/to/media.mp3 (or https://... if you are using SSL). Setting a base_url that contains the IP address of your server works around this issue. By using an IP address, the cast device does not have to resolve the hostname.

An alternative way to force Google cast devices to use internal DNS is to block them from accessing Google DNS at the firewall/router level. This would be useful in the case, for example, where your internal IP of HASS is a private IP and you have your internal DNS server (quite often a split-brain DNS scenario). This method works on both Google Home Mini and Google Chromecasts.

Service say

The say service support language and on some platforms also options for set, i.e., voice, motion, speed, etc. The text for speech is set with message. Since release 0.92, service name can be defined in configuration service_name option.

Say to all media_player device entities:

# Replace google_translate_say with <platform>_say when you use a different platform.
service: tts.google_translate_say
entity_id: "all"
data:
message: 'May the Force be with you.'

Cache

The integration has two caches. Both caches can be controlled with the cache option in the platform configuration or the service call say. A long time cache will be located on the file system. The in-memory cache for fast responses to media players will be auto-cleaned after a short period.

REST Api

POST /api/tts_get_url

Returns an URL to the generated TTS file. Platform and message are required.

{
"platform": "amazon_polly",
"message": "I am speaking now"
}

The return code is 200 if the file is generated. The message body will contain a JSON object with the URL.